Method of manufacturing leather goods and the like

ABSTRACT

Method of and apparatus for manufacturing goods made of leather or like material in which a flat piece of the material, preconditioned to be readily deformable, is located between a diaphragm and a former, the diaphragm is moved to nip the material between the diaphragm and the former, the locating means is removed, the diaphragm is moved towards the former until a frame in which it is held makes a vacuum-tight seal with a table on which the former is mounted, and vacuum is applied to cause the diaphragm to draw and shape the material closely around the former.

United States Patent White et al. Sept. 5, 1972 [54] METHOD OFMANUFACTURING [56] References Cited LEATHER GOODS AND THE LIKE UNITEDSTATES PATENTS [72] Invemms Raymnd ,Charles white f 3,397,418 8/1968Steadman et al 12/146 0 T Dallngmn Bath; 3,445,873 5/1969 Staden 12/1460 ham Frank Walker, 8, Friars Close, Croyland Park wenmgborough PrimaryExaminer-Patrick D. Lawson both of England Attorney-Emory L. Groff andEmory L. Groff, Jr. [22] Filed: March 19, 1971 [57] ABSTRACT [21] Appl.No.: 126,042

Method of and apparatus for manufacturing goods 4 made of leather orlike material in which a flat piece 30 F A u ti M Data of the material,preconditioned to be readily deforma- 1 orelgn pp ca on y ble, islocated between a diaphragm and a former, the p 1970 Great Bl'ltalndiaphragm is moved to nip the material between the diaphragm and theformer, the locating means is removed, the diaphragm is moved towardsthe former (g1. ..12/l46Ag3(ll21/i;46(2) until a frame in which it isheld makes a vacuum-4m, I o 6 6 6 6 6 6 6 6 6 e I n a] h t h h f d d[58] Field 6: Search ..12/146 R, 146 c, 146 D, 21, Se a a e on w 8 0mmmoume vacuum is applied to cause the diaphragm to draw and shape thematerial closely around the former.

4 Claims, 10 Drawing Figures METHOD OF MANUFACTURING LEATHER GOODS ANDTHE LIKE This invention relates to the manufacture of articles made fromleather, synthetic plastics, bonded or woven fiber, paper or othermaterials which may simulate leather, even to the extent that they arevery slightly porous and are said to breathe. One such material, madefrom polyurethane, is known by the registered trademark Porvair.

The invention is particularly useful in the manufacture of boots andshoes but may be applied to the manufacture of other types of leathergoods. Similarly it may be applied to the manufacture of boots and shoesor other goods which are made from synthetic plastics, bonded fiber,paper or other materials which simulate leather. The term or the like"is used to embrace all these variations.

In the manufacture of shoes, the method as generally practiced atpresent is first to construct the upper and for this purpose shapedpieces are cut from a sheet of leather or the like.

One or more of the pieces may be partly preformed, that is, shaped bytreating each piece with heat and/or steam, or otherwise, to make itreadily deformable, and then clamping it in a shaped die. The pieces arethen sewn or bonded together so that a substantially complete upper isprovided, and linings are attached to the inside surface if desired. Alast of the shape of shoe to be made has an insole attached to it, theupper is placed upon it and the assembly is placed in a machine in whichthe edges of the upper are pulled underneath the edges of the last andover the insole. Heating, which may be high frequency, and/orconditioning by steam, may be applied so that when the operation hasbeen completed the upper conforms to the shape ofthe last. The edges ofthe upper which have been pulled under the last vary considerably inwidth and are creased and puckered, and they are attached to the undersurface of the insole, usually by nailing or adhesives. The uneven,creased and puckered edges of the piece at the under surface of the lastare next ground away so that the creases and puckers disappear and theedges are roughened to accept an adhesive for sole attachment.

Numerous operations are necessary up to the stage described above andsince the last must remain in the shoe beyond the stage covered by theforegoing description and up to an advanced stage of manufacture, it isnecessary to stock a large number of pairs of lasts for each size andshape of shoe which is to be manufactured, to ensure that during a longproduction run the factory is not brought to a halt by a shortage oflasts.

The principal object of the invention is to provide a simplified andimproved method of manufacture of footwear, such as boots and shoes, andother leather goods and the like, in which the number of operationsnecessary is reduced and a minimum number of formers is used to producean article, which article conforms more accurately to the desired shapeand is better adapted to mass production.

The invention consists of a method of manufacturing goods made of amaterial such as leather or a leather substitute or like materialcomprising the steps of providing a former having the shape and size towhich it is desired to form the material, cutting a piece of thematerial in flat form to a shape such that when formed over the formerit will have the desired shape and dimensions, conditioning the materialso that it will readily deform when drawn over the former, suspendingthe piece of material in juxtaposition to the former, placing a flexibleand expansible diaphragm near the outside of the material so that thematerial lies between the former and the diaphragm, moving the materialinto contact with the former and moving the diaphragm into contact withthe material so that the material is interleaved between the former andthe diaphragm and is held in accurate location with respect to theformer, removing the means by which the material is suspended, andapplying a vacuum between the former and the diaphragm so that thediaphragm and the material are closely drawn around the former.

Conveniently the former is fixed to a horizontal table having aperipheral vacuum sealing edge, the material is suspended above theformer in a horizontal plane by means of finger clamps, retaining pins,clips, adhesive, vacuum or pressure depending upon the material beingused and the final shape, which are disengaged and withdrawn after thematerial has been held in its correct location between the former andthe diaphragm, and the diaphragm is attached to a horizontal framehaving a lower vacuum sealing edge around the periphery of its undersidewhich engages the peripheral sealing edge of the table when the frame islowered.

One method according to the invention will now be described, by way ofexample, with reference to the accompanying drawing in which:

FIG. 1 is a diagrammatic elevation partly in section, of the apparatusused to carry out the method;

FIG. 2 is a view of a piece of material cut to a shape which, whenformed, will provide an article having the desired shape and dimensions;

FIG. 3 is a view of the bottom of a shoe upper;

FIG. 4 is a side elevation of a support for a fore-part former;

FIG. Sis a side elevation of the support of FIG. 4;

FIG. 6 is a plan view of the support of FIGS. 4 and 5;

FIG. 7 is a pictorial view of the former, support and diaphragm for aformer for producing full backs of shoes;

FIG. 8 is a wide elevation of the former shown in FIG. 7;

FIG. 9 is an end elevation of the former of FIG. 8, also showing thediaphragm; and

FIG. 10 is an enlarged view of a small part of the diaphragm support ofFIGS. 7 and 9 showing how the diaphragm is clamped in position.

Referring to the drawings, a suitable apparatus for carrying out theinvention in relation to the manufacture of shoes comprises a horizontaltable 11 having an upstanding peripheral edge 12 whose upper surface 13will, in conjunction with a mating surface, form a vacuum seal. Aformer, generally indicated by reference 14, is so shaped as to definethe fore-parts of two shoe uppers joined together, one being indicatedby reference 15 and the other by reference 16.

Since two shoe upper fore-parts are to be formed in one operation theformer is so shaped that one upper fore-part is for a left shoe and theother is for a right shoe of the same size and matching fitting. Theformer is mounted on the table by a small platform 17. A tube 18 forms aconnection to vacuum equipment and is connected with ducts or channels(not shown) by which the outer part of the former is placed incommunication with the vacuum equipment. FIG. 2 shows the shape of apiece 19 of material for a particular shape and size of shoe, drawn to alarger scale than FIG. 1. It includes a tongue portion 20, and thepoints at which finger clamps may be attached are shown dotted at 21, 22and 23. It will be evident that if a moderate pull is exerted on each ofthese clamps the piece 19 will be kept reasonably taut and if the clampsare correctly located the piece 19 may be located with equal accuracy.An aperture such as a small slot or hole may be punched at each of theclamping points, as indicated at 24, and the finger clamps may includesmall pins to promote accuracy in location. If the outer, tanned,surface (in the case of a piece of leather) is uppermost in H0. 2 thenthe resulting upper will be for a left shoe and if the tanned surface isunderneath then the upper will be for a right shoe.

Two pieces, as shown in FIG. 2, to form a pair of upper fore-parts orvamps, are engaged by finger clamps such as those shown at 25, 26, 27,and 28, and two more which are not seen. By means of the finger clampsthe pieces are accurately located above the former 14. A frame,generally indicated at 29, is of the same overall size as the peripheralportion 12 of the table 11 and has a lower surface 30 which, whenengaged with the surface 13, will form a vacuum seal. Clamped in theframe 29 is a diaphragm 31 which is made of a flexible and expansiblematerial such as rubber latex. At any suitable point in the procedure,the pieces are conditioned, by heating if purely thermoplastic, or bythe application of moist heat, for example by steaming, so that theywill readily distort and conform to the shape of the former.

To carry out the forming operation a carrier by which the finger clamps,and hence the pieces of material, are carried, is lowered until thepieces of material touch the former at one or more points. The frame 29is then lowered until the diaphragm 31 is in contact with the pieces ofmaterial so that the material is nipped and lightly held in its correctlocation. The finger clamps are then removed and the frame 29 is lowereduntil the surface 30 engages the surface 13 to provide a vacuum seal.Vacuum is applied so that the diaphragm is drawn downwardly and formsand draws the pieces of material closely around the former and turns theedges over to lie against a marginal undersurface of the former at 32.

The apparatus is then left for a time sufiicient for the pieces ofmaterial to cool, whereupon the vacuum may be released and the apparatusopened to allow removal of the formed fore-parts or varnps.

By the simple process described above it is possible to produce the twovamps for a pair of shoes.

FIG. 3 shows a view of the bottom of a formed vamp, the shape showingonly the marginal or edge portion 33 which is formed against themarginal undersurface 32 of the former. An important characteristic ofthis marginal portion is that it is of uniform width and accuratelyshaped, which simplifies later operations in the manufacture of theshoes.

Since the process according to the invention minimizes the creases orpuckers and the marginal portion is of uniform width no initial grindingaway is required and the vamp (with a lining if this is required) may becemented or welded to a sole, an insole being inserted and cemented orwelded into place afterwards. Naturally, variations in the processdescribed above may be made within the scope of the invention.

The shape of upper shown in FIG. 3 has deliberately been chosen as onewhich includes rather sharp bends. In order to make quite sure thatthere can be no creasing or puckering of the marginal undersurface 33 ofthe formed piece small nicks, indicated at 34, may be made in the pieceswhen they are first cut to shape. For the particular shoe for which theupper shown in FIG. 3 is required the portion of the margin at 35 willbe turned into the position shown dotted at 36 when the upper is placedon a foot former for a subsequent operation, such as welding on of asole, and nicks 37 may be provided to ensure that there is no puckeringas the part is turned in. It will be understood that other components ofa shoe upper may also be formed, singly or in pairs or other multiples,by the use of appropriate formers.

ln forming a complex shape such as a shoe upper or a full back (that isto say, the rear part of a shoe which is made in one piece without theusual vertical seam at the back) it is often desirable to shape thesupport on which the former is carried in such a way as to facilitatethe movement of the diaphragm on the one hand, so that it makes intimatecontact with the former and the support without becoming crinkled and,on the other hand, without being excessively stretched at any point. Itmay also be desirable to support the diaphragm in such a way that,instead of being flat, it has a desired configuration to suit the shapeof the former. Examples of such shaping of the support and configurationof the diaphragm are shown in FIGS. 4 to 6 and 7 to 10. In FIGS. 4 to 6the support for the former is generally indicated by reference 38, theformer being indicated in dotted lines at 39. In plan the support hasthe general shape of the former but is cut back all round. The uppercontour is indicated at 40 and 41 and, as shown at 42 and 43, the endsare sloped, the sides of the support being also sloped, as indicated at44 and 45. The contour as seen in plan is indicated in FIGS. 5 and 6,the contour of the upper surface of the support being shown at 46 andthe contour of the lower surface being shown at 47.

FIG. 7 is a pictorial view of the former and diaphragm for forming fullbacks for a pair of shoes, which may or may not have a vertical seam atthe rear. The base of the former is indicated at 48. Two end pieces,respectively 49 and 50, are shaped to make a vacuum tight joint with acurved portion 51 at each end of a framework 53 which supports thediaphragm 52. The framework 53 is in two parts to enable the edges ofthe diaphragm to be clamped between them and the framework is so shapedthat the configuration of the diaphragm suits the shape of the former.One support 54 by which the framework 53 is carried is shown. The othersupports and a number of clamping screws have been omitted in FIG. 7 butare shown in later Figures. The former itself consists of two parts,respectively 55 and 56, which are joined together, and an elevation ofthe former parts 55 and 56 is shown in FIG. 8, the diaphragm and itssupporting framework being omitted in the last-mentioned Figure.

As shown in FIG. 8, the former parts 55 and 56 are formed to produce twofull backs, one for a right shoe and one for a left shoe. The end pieces49 and 50 are shown and it will be observed that the former parts 55 and56 are provided with end supports, respectively 57 and 58, which areshaped in such a manner that the diaphragm is not excessively stretchedand at the same time will not become crinkled when it is drawn over theformer parts 55 and 56. The base 48 of the former is also shown in FIG.8. The manner in which vacuum may be applied will be obvious from theforegoing description of FIG. 1.

FiG. 9 is an end view of the former assembly of FIGS. 7 and 8 and showsthe diaphragm with its framework. The base 48, end piece 50 and theformer part 56 are shown in FIG. 9, together with the framework 53 whichis in two mating parts to enable the diaphragm to be clamped betweenthem by means of nuts on the supports 54, of which there are four, andadditional screws and wingnuts 59. One end of the framework 53 is showndrawn to a slightly larger scale in FIG. 10. This includes one of thesupports 54 and screws and wingnuts 59 which are placed at intervalsaround the framework 53 so that the diaphragm 52 may be securelyclamped. it will be noted from FIGS. 7 and 10 that the diaphragm 52 isnot necessarily stretched when in the framework 53 and it may beadvantageous in fixing the diaphragm into the framework 53 to leave itsomewhat slacker or looser in some places than in others, depending uponthe shape of the mould and the amount of stretching to which differentparts of the diaphragm will be subjected in actual operation. Attentionto such matters increases the life of the diaphragm when in actualoperation.

Similarly, parts for other kinds of leather goods or the like may beformed by the use of the method according to the invention.

We claim:

1. A method of manufacturing goods made of a material such as leather ora leather substitute or like material comprising the steps of providinga former having the shape and size to which it is desired to form thematerial, cutting a piece of the material in flat form to a shape suchthat when formed over the former it will have the desired shape anddimensions, conditioning the material so that it will readily deformwhen drawn over the former, suspending the piece of material injuxtaposition to the former, placing a flexible and expansible diaphragmnear the outside of the material so that the material lies between theformer and the diaphragm, moving the material into contact with theformer and moving the diaphragm into contact with the material so thatthe material is interleaved between the former and the diaphragm and isheld in accurate location with respect to the former, removing the meansby which the material is suspended, and applying a vacuum between theformer and the diaphragm so that the diaphragm and the material areclosely drawn around the former.

2. A method as claimed in claim 1 comprising the step of making a formerhaving the shape and size of a plurality of pieces of material, cuttingthe said plurality of pieces of material, suspending the plurality ofpieces of material in correct location with respect to the former and toeach oth r moving the material and diaphragm so that each 0 the pluraity of pieces is held in accurate location with respect to the former,whereby the application of vacuum will cause all the pieces of materialto be closely drawn around the respective areas of the former.

3. A method as claimed in claim 1 comprising the step of so placing thediaphragm that its initial configuration if accommodated to the shape ofthe former.

4. A method as claimed in claim 1 comprising the step of forming the oreach piece of material with apertures and suspending the material bymeans of removable clips which engage the aperture.

1. A method of manufacturing goods made of a material such as leather ora leather substitute or like material comprising the steps of providinga former having the shape and size to which it is desired to form thematerial, cutting a piece of the material in flat form to a shape suchthat when formed over the former it will have the desired shape anddimensions, conditioning the material so that it will readily deformwhen drawn over the former, suspending the piece of material injuxtaposition to the former, placing a flexible and expansible diaphragmnear the outside of the material so that the material lies between theformer and the diaphragm, moving the material into contact with theformer and moving the diaphragm into contact with the material so thatthe material is interleaved between the former and the diaphragm and isheld in accurate location with respect to the former, removing the meansby which the material is suspended, and applying a vacuum between theformer and the diaphragm so that the diaphragm and the material areclosely drawn around the former.
 2. A method as claimed in claim 1comprising the step of making a former having the shape and size of aplurality of pieces of material, cutting the said plurality of pieces ofmaterial, suspending the plurality of pieces of material in correctlocation with respect to the former and to each other, moving thematerial and diaphragm so that each of the plurality of pieces is heldin accurate location with respect to the former, whereby the applicationof vacuum will cause all the pieces of material to be closely drawnaround the respective areas of the former.
 3. A method as claimed inclaim 1 comprising the step of so placing the diaphragm that its initialconfiguration if accommodated to the shape of the former.
 4. A method asclaimed in claim 1 comprising the step of forming the or each piece ofmaterial with apertures and suspending the material by means ofremovable clips which engage the aperture.